Really bad vibration

I have an 06 extreme LT that has a really bad rattle between 2100-2400 rpm. It sounds like it is coming from the exhaust but i can not find from where. Just wondering if anybody has had the same problem and if yes what was the fix.

I believe mine has the same problem.I posted something about it and a friend said it was the inside of the cat vibrating on its case.I was going to change it and never did.I don't believe it is the cat anymore.Mine is like a hum or a vvvVVVEERRRRt that can also be felt and when I got the truck it was only between 800-900 rpm...now it's 1000 rpm on the dot and again around 2100-2300.It also does it in park so it's not a drive thing.Does this sound like what you have?Maybe between the two of us we can figure it out.

I have an 06 extreme LT that has a really bad rattle between 2100-2400 rpm. It sounds like it is coming from the exhaust but i can not find from where. Just wondering if anybody has had the same problem and if yes what was the fix.

Click to expand...

--- check the heat sheild on top of the muffler / resonator / cat....at certain RPM's, the sheild/pipe section will flex / rise----you will need a helper to watch for rattles / noise as you slowly press the accelerator to find the rattle------you could also look for broken bolt head in the exhaust flange in the engine area---won't let go, but will rattle until rust eventually wins over ( from silverhobey)

--- check the heat sheild on top of the muffler / resonator / cat....at certain RPM's, the sheild/pipe section will flex / rise----you will need a helper to watch for rattles / noise as you slowly press the accelerator to find the rattle------you could also look for broken bolt head in the exhaust flange in the engine area---won't let go, but will rattle until rust eventually wins over ( from silverhobey)

Click to expand...

I forgot to mention that I didn't have anyone that would help me so one day I used my predator to set my idle right at 1000 rpm so the noise would be constant and I could investigate.As soon as I step out of the truck the noise is unhearable...I think something like the engine may be vibrating and for some reason something in the cab is actually making the noise because of it.Very weird and hard to find.Btw I can feel it in the steering wheel and if I look in my rear veiw mirror it looks like I have a subwoofer going.

This could be a long shot for you, but may solve your problem. I thought I had the same issue sounded like a really loud metal on metal rattle from near the muffler. Come to find out the U-joints on the drive shaft were bad. Replaced those and never heard the noise again. If the problem hasn't been fixed may be worth taking a look at!